Percussive rock-drilling apparatus.



R. H. ADAMS.

PERCUSSWE ROCK DRILLING APPARATUS. APPLICATION FILED MAY 10. 1917.-

1,269, 1 47. Patented June 11, 1918;

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R. H. ADAMS.

PEREUSSIVE ROCK DRILLING APPARATUS. APPLICATION FILED MAY 10. m1.

1 ,26 9, 1 4:7. Patented June 11, 1918.

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w R. H. ADAMS.

PERCUSSLVE ROCK DRILLING APPARATUS.

APPLICATION FILED MAY 10. 1911.'

1,269,147. PatentedJl me 11, 1918.

3 SHEETS-SHEET 3.

' UNITED sTATEs PATENT OFFICE.

RICHARD HENRY ADAMS, OF COBALT, ONTARIO, CANADA.

PERCUSSIVE ROCK-DRILLING APPARATUS.

Specification of Letters Patent.

Patented June 11, 1918.

Application filed May 10, 1917. Serial No. 167,650.

To all whom it may concern Be -it known that I, RICHARD HENRY Annn's, a subject of the King of Great Britain, residing at the town of Cobalt, in the county of Nipissing and Province of Ontario, Dominion of Canada, have invented certain new and useful Improvements in Pcrcussive Rock-Drilling= Apparatus; and I hereby declare that the following is a full, clear, and exact description of the same.

This invention relates to a percussive rock drilling apparatus containing certain novel features of construction which permit of from the air chest transversely through the cylinder and its surrounding acket, and by providing the air chest with a tubular air container having ports which, during the reciprocation of the container, register alternately with said air inlct'ports and feed the compressed air therethrough, the cylinder being provided with reversing ports by which the air container is actuated to feed the air alternately to said inlet ports;

(7)) To certain details in the construction of the cylinder and the means provided for scavenging theair when the piston reverses its movement;

(0) To the rotating device by which the piston can be caused to either revolve or gyrate during the operation of the drill;

(d) To providing the front end of the cylinder with a countersunk seat for the front cylinder head and thus eliminate any structural feature from the interior of the cylinder tending to eitheri'nterfere with the operation of the'piston 'or to result in the injury or destruction of the apparatus;

(e) To the means by which the drill is secured to the drillstock, such means consisting of a movable key con'ipressed against the drill shank by means of a chuck having a tapering chamber so disposed with relation to the drill stock that the percussive action of the drill tends to tighten the pressure of the chuck against the key and the corresponding pressure of the key against the drill shank;

(7') To preventing the leakage of air past the piston heads by constructing the piston rings of two semi-circular sections, so that.

they can be easily fitted into the piston grooves, and providing each section with,

projecting tongues, Which, when the piston rings are assembled, will overlap the correspending tongues of the other section; and,

(9) To providing the shell with laterallyadjustable slideways, by which the Wear, either of the slides or the slideways, may be taken up to prevent the lateral movement of the cylinder, whilepermitting of its free axial movement.

In the draW1ngs:-

Figure 1, is a sectional elevation of the cylinder and its related parts;

Fig. 2, is an end elevation of the slide; Fig. 3, is a side elevation of the slide; Fig. 4:, is a plan view of the slide; Figs. 5 and 6, are detail views of the piston ring; and,

Fig. 7, is a sectional elevation of the cylinder with the piston removed.

Like characters of reference refer to like parts throughout the specification and drawings. v I

a represents the cylinder, which is of the usual shape and dimensions; 6 represents a jacket surrounding the cylinder a, and forming with it an exhaust chamber a; and d represents an air chest, integral with, or attached to the jacket I), provided'with an air intake '6. i Y

'Within the air chest d is a tubular air container 7 having a port 9 through which the .air flows, continuing from the air intake 6 into the container, this port being elliptical or elongated, so that a part of it will always be in line with the air intake 6, re gardless of the position of the tubular air container during its stroke. The ends of the air container 7 areclosed by heads it, h, and formed through the Wall of the air con tainer adjacent to the heads it, h, are ports 2', t" which register during the stroke of the valve with corresponding ports j, respectively, leading directly from the air chest into the cylinder in the vicinity of the front and back heads k, 70, respectively. -The length of the ports 7c, is is relatively short, so that there will be no storage therein of any considerable quantity of compressed air during'the operation of the apparatus,to be wasted during the exhaust.

In a full-sized apparatus, these ports is, is

wire from three-quarter .inch to an inch in length, one-quarter inch in depth, and about .v one and one-quarter inches -in width, which ofabout'tWenty-four times that of the present construction.

' chest wit h the structuralparts of the con- 'ta-iner; I v i The outer surface" of the Wall of the air container fiS' apertured, as shown at Z, to

reduce ythe weight of the container, the air being unable to find an outletthrough the apertures Z, owing to the contact of the air The Wall of the container 7", adjacent to the ports 2', i, is recessed as shown at m, m,

' and leading through the jacket I) to the extional area of the cylinder, there can be no haust chamber 0, are ports 0, 0 with which these recesses m, m register during the movement of the air container, the ports 0, 0' being contiguous to the ports 9', j, so that the"recesses m, m may, during the strol t of the container, couple the ports j and, o", and the-ports j and 0, respectively,

to enable the air within the cylinder being fo iced out through the ports j, j to the recesses m, m. and through the ports 0, 0 to the exhaust chamber 0, from which it escapes by means of the exhaust ports 32,

As the ports j, j, 0,0 and p, p are relatively small in proportion to the cross-seesudden expansion during the return naive ment of the piston, resulting from the exhaus't of the compressed air through the ports j, j and 0, 0 into the exhaust chamber c, nor any sudden expansion of the air as it passes from the exhaust chamber 0 through theexhaust ports p, p to the atmosphere. In this way, a substantially uniform temperature is, maintained in the cylinder,the maintenance of which prevents the piston and cylinder freezing together, and enables the apparatus to continuously opcrateunder normal conditions.

In tne back cylinder head and in line with the inlet port j, is an air chamber 9, having a set of diagonally-arranged, ports 9'.

to deliver the air on the backFp-iston'head T,

which is provided with a turbine orrotatmg device 7*. Between the piston heads 7;

and s, is'the gyrator t, which consists of a set of spiral grooves tand a nut 25. The inner face of the nut t is provided with teeth '6', which enter the spiralgrooves t to cause the gyration of the pitton, and its outer surface is provided withratchet teeth a engaged by pawls 4/ which permit of the forward gyration of the piston'and prevent its reverse 'gy'ration. The pawls o are carried by forks oj extended into the cylinder from the exterior of the apparatus, the forks engaging the nut' t to'prevent its axial movement during the reciprocation ofthe piston, and to permit of its forward, and

ration of the piston. By this means, a partial rotation of the piston may be effected at each stroke of the piston.

the front part of the. cylinder into the air chest near its back head, and the air ductwf' leading from the back part of the cylindet into the air chest near its front head.

The air enteringthe air chest at through the .aii; intake 6, passes through the port 9 into the tubular air container 7, and when the port 2' is in line with the, port 1, passes into the cylinder a in. the "icinity of the front cylinder head 7:, against which it operates tdfbrce the piston in the direction of the back cylinder head is".

When the front piston head 8 clears the port of the air duct 10, some of the air 'with- .75 prevent the reverse, rotation during the gyin the front part of the cylinder passes through the duct w into the air chest d at the bark of the container head/t" and forces the container in a forward dlrection, as 111- (heated by arrow in 1.

This movement of" the container brings the port 1' out of line with the port j and brings the port i into] linewith the port j, and the recess 0);, into position to couple the port j with the port p. The compressed air then flows through the ports 71 'and 7" into the air chan'lber q, from which it is directed by the ports 9' against the back piston head 1, to cause the rotation of the piston and drive it in the direction of the front cylinder head. While the piston is moving in the direction of the front-cylinder head, the front piston head 3 force s-the air in the front part 'of the cylinder through the port 2', recess 'm,

port j, to the exhaust chamber, out of which it passes through the exhaust ports 37, p.

\Vhen the front piston head passes the port for the air duct w, the air in that duct can find a passage around the gyrator t to the exhaust port so for the cylinder (1,

through which i-t escapes to theatmosphere,

there being a space between the gyrator and the cylinder wall of suiiicient dimensions to admit of the air in the ducts w, w and in the air chest between the container and the chest heads, being immediately exhausted during the cycle of action.

When the back piston head 1 passes the port for the air duct w, the air passes from the back part of the cylinder through the duct w into the air chest in front of the container head It, and moves the container in the opposite direction to that indicated by arrow in Fig. 1. i 4

This has theeffect of moving the port 2" out of line with the port j andbringing the port 2' again into linewith the port, j and the recess m into position to couple the ports j and 0, so that when the piston is reversing its movement, z'. 6., moving in the direction of the back cylinder head, the air will be scavenged through the ports j and 0 to the chamber 0 and escape through the exhaust ports 1), p. I

This action of the air container has the cf fect of supplying only suificient air to the cylinder to move the piston to the limit of its stroke in either direction, and avoids the accumulation in the passages or ports lead,-

ing from the air chest to the cylinder, of a quantity of compressed air which is not used for driving purposes. The economy in operation, and saves about fifty per cent.

of the operating charges.

To prevent a leakage past the piston headsy'these heads are grooved, as shown at a, and contained in the grooves are piston rings bl, similar to those shownin Figs. 5 and 6, each of these piston rings consisting of two semi-circular sections, each semi-circularsection having a lap-joint b corresponding with the lap-joints of the other section, so that no channel will be formed, even as a result of the wear on these parts, through which the air can escape past the piston heads; it being necessary to make them in two sections, each of which can be independently fitted in its groove, 'as the weight and inclast-icity of the ring prevents it being sprung into position, as in the case of ordinary piston rings.

All of the foregoing features contribute to the economy of operation, and it has been estimated that the saving in compressed air alone averages one hundred and fifty dollars per month per drill.

The piston rod 0 extends beyond the front piston head 8, and is formed with a fillet c" in front of the piston head to strengthen it. The front cylinder head inis formed with a correspondingly-sheped bevel 0, so that when the piston reaches the limit of its stroke in a downward direction. the fillet will enter the bevel a, but without coming in contact with the front cylinder head, but if it should drive past-the limit of its stroke, the feature of the fillet and the bevel will prevent any serious damage being done to the front cylinder head, as no projecting part of the cylinder head, such as a boss, is pre sented to the piston head to, be riveted or hammered during the cycle of action.

To maintain the correct alinement' of the front cylinder head, the cylinder is formed with a countersunk seat f at its front end, into which the front cylinder head enters, this countersunk seat holding the front 'cylinder head in its set position without presenting any interior parts to the front piston head, thus obviating the trouble which has heretofore arisen through the presence of an interior boss on the front cylinder head within the cylinder, such boss usually being hannuered by the front piston head during the movement of the piston until a breakage occurs, and the drill is put out of action.

The drill stock 5/ is circumferentially apertured at 1 for the wedge Z", which engages the drill shank when inserted in the drill stock, the wedge Z having a head Z and beingengaged i a cylindrical chuck s. This chuck 8 consists of a cylindrical wall 8, and end flanges 1 having a central bore d2 of corresponding diameter to the drill stock, so that the chuck will snugly fit thereon.

The interior surface of the Wall 8 is tapered with its contracted end toward the back of the drill stock, to engage and coinpress the Wedge adjacent the drill shank as the wedge and limiting the movement of the chuck in either direction on the drill stock. To insert the drill shank into the drill stock, the chuck is moved toward the front cylinder head, which movement continually increases the diameter of the interior surface of the wall 8 until the chuck has reached its limit of movement in that direction. the maximum internal diameter of the chuck then being sufiicient to release the pressure of the wedge from the drill shank. I

When the chuck is 'in this position, the drill shank can either be inserted in or withdrawn from the drill stock. Whcn the drill shank is inserted in the drill stock, the movement of the chuck is reversed, and the wall of the chuck continually contracts upon the w dge, til no further movement is-pbssible, and securely clamps the drill shankin the drill stock.

During the operation OI the apparatus, the striking of the drillou the rock has the tendency to increase the pressure of the chuck against the wedge, and the wedge against the .drill shank, until no further pressure is possible, it being necessary to release the chuck by pounding it with a softmetal hammer.

' One of the sources of niostfrequent trouble is the wear on the fixed slides of the cylinder and slideways of the shell, this wear permitting of the lateral movement of the" cylinder.

To overcome this, I have provided the shell with adjustable slideways 1, and to accomplish the adjustment, .1 have formed the body of the shell with elongated slots .2, disposed transversely to the length of the shell, and, have provided the 'slideways=with adjusting bolts .2 which are in.-

serted through these slots to permit of the lateral adjustment of the slideways to each I other and to the slides a of the cylinder. This lateral adjustment keepsthe slides and slideway's" constantly in contact with each other, and in this way, prevents any side movement during either the adjustment of the cylinder or the operation of the appai ratus; 7

While this may appear, in itself, a trivial alteration, still, it is of the utmost'importance, in view of the fact that it is necessary for the drill to strike the same spot operation of the piston.

Having thus fully described the nature of:

my invention, what I claim as new and desire to secure by Letters Patent, is

1. A percussive rock-drilling apparatus comprising a cylinder having a piston there in and a central exhaust port Within the boundaries of the stroke of the piston heads,

' a jacket surrounding the cylinder, and forming with it an exhaust chamber having outlet ports, an air chest having inlet ports into the cylinder ad acent to the cyllnder head and exhaust ports into the exhaust chamher in the vicinity of the inlet ports, and

valve-reversing ports in the vicinity of the air-chest-heads leading to opposite sides of the center of the piston stroke, and a reciprocating tubular air-valve in the air-chest having portsregistering with the inlet. ports of the cylinder and recesses in its cylindrical wall coupling the inlet and exhaust ports during the reciprocation of the valve. 7

'2.- A percussive rock drilling apparatus at each tamer Within the air chest having ports regcomprising a cylinder having an inlet port adjacent to each cylinder head, an air chest for the cylinder having an air intake, a tubular air container within the air chest having a port through which. the air flows into; it

continuously from the air intake, the ends of the container being closed and the wall of- .the container being provided with ports to register'during the cycle of action withv the ports leading into the cylinder, the wall of said container being recessed in the vicinity of said ports, and an exhaust chamber surrounding the cylinder having exhaust ports leading to the atmosphere and ports 'communicating with the air chest in the vicinity of the inlet ports for the cylinder and coupled therewith by the recesses in the wall of the container during the cycle of action.

comprising a cylinder, a piston therein, an

relatively short inlet ports leading direct into the cylinder in thevicinity of the cylinder heads, a reciprocating tubular air conistering during its'reciprocation alternately with said air inlet ports, and reversing ports leading from the cylinder to the air chest, controlled during the cycle of action by the piston, to cause the tubular air container to 3. A percussive rock drilling apparatus vair chestconneeted with the cylinder by reciprocate alternately in opposite directions, an exhaust for the reversing ports, an exhaust chamber surrounding the cylinder, having exhaust ports leading to the atmosphere and ports communicating with the air chest in the vicinity of the inlet ports for the cylinder, and coupled therewith by recesses in the wall of said container, during the cycle of action, to rovide for the scavenging of the cylinder uring the reversal of the piston.

Toronto, April 10th, 1917.

RICHARD HENRY ADAMS.

- Signed int-he presence of EDWARD S. BERNSTEIN, CHAS. H. 'RIGHESH 

